A variety of push-button actuated dispensing valves for dispensing liquids from a relatively large capacity container are known in the art. Where the dispensing valve or tap is used with a flexible wall container, it is not necessary the container be vented in any way because no pressure differential is created upon the emptying of the container through the tap.
However, with a rigid container, a system must be provided for equalizing the pressure differential created as contents of the rigid wall container are extracted. Such a vent may be remote from the dispensing valve and may merely comprise a capped opening in an upper wall of the container which, when uncapped, permits ingress of air into the volume as the liquid contents of the container are being dispensed. Also known in the prior art are self-venting valves eliminating the need for a separate, remote vent opening in the container. Listed below are a number of prior art patents relating to self-venting dispensing valve structures. Those with knowledge of dispensing art will recognize with the discussion below how embodiments of the present invention not only differ, but how embodiments of the present invention provide for a much more functional liquid dispenser.
Wight686,566Terkel2,197,352Duval et al.2,842,291Freemon2,113,046Collins1,749,970Berkus3,372,846Damrel3,405,848Kalis, et al5,405,058Rudick4,898,308Stumpf4,930,689Vachon6,155,464Lucking et al.5,211,313White5,332,127Roll et al5,606,989Paczonay5,927,565Paczonay6,364,178Blackbourn et al.6,401,752Blackbourn et al.6,470,910Laible6,968,983Labinski et al.7,513,395DiegoWO 2007108025
It would be desirable to have a low cost, easy to assemble, reliably operating, mess-free dispensing valve for a rigid container, which will work well with both viscous and low viscosity liquids.